Researchers from École Polytechnique Fédérale de Lausanne (EPFL), University of Applied Sciences and Arts of Western Switzerland and Politecnico di Milano have designed a highly efficient and stable perovskite solar cell using a new approach that combines a simple chemical additive, TEMPO, with a rapid infrared curing process.
This method produced a high-performance, stable formamidinium lead iodide (FAPI) perovskite solar cell (PSC) through the use of 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO) bulk passivation and rapid photonic annealing. Using flash infrared annealing (FIRA), the team fabricated TEMPO-FAPI PSCs with a power conversion efficiency (PCE) exceeding 20%.
The TEMPO additive promotes enhanced crystallization dynamics, yielding films with improved homogeneity and reduced defect densities, as confirmed by photoluminescence (PL), profilometry, and positron annihilation lifetime spectroscopy (PALS).
Stability testing under ISOS protocols demonstrated that the TEMPO-FAPI devices retained over 90% of their initial PCE after 4,296 h of operational and thermal stress, showing unprecedented longevity for a rapid processing technique.
TEMPO’s primary effect on passivating grain boundaries and surface defects is evidenced by a significantly reduced non-radiative recombination rate and low defect density, establishing this molecule as a promising additive for scalable, durable FAPI PSC manufacturing.
In this recent work, the scientists demonstrated that integrating additive-based passivation with rapid annealing can provide a scalable approach to manufacturing durable, high-performance perovskite solar cells, marking a step forward in the commercial viability of perovskite-based photovoltaics.
